<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Pseudo</title>
    <link rel="stylesheet" href="Pseudo.css">
</head>

<body>
    <!-- 伪类选择器 -->

    <!-- 1、a标签的伪类 -->
    <div class="a">
        <a href="#">这是一个a标签</a>
    </div>

    <!-- 2、input获取焦点 -->
    <div class="input">
        <input type="text" placeholder="点我点我">
    </div>

    <!-- 3、hover -->
    <div class="father">
        <span>鼠标移到这里～</span>
        <div class="son"></div>
    </div>

    <!-- 伪元素选择器 -->

    <!-- 实现小三角 -->
    <!-- <p class="arrow-right">作业做了吗？</p> -->
</body>

</html>